Veritas Storage Foundation Intelligent Storage Provisioning 5.0.1 Administrators Guide, HP-UX 11i v3, First Edition, November 2009

By allowing ISP to choose any template that provides the required capability, the
requires keyword gives ISP more flexibility when allocating storage. This behavior
is known as dynamic inheritance.
When choosing a template with a required capability, ISP gives preference to
templates that provide only that capability. This behavior avoids giving unrelated
capabilities to a volume.
When searching for a template with a required capability, ISP chooses only those
templates that inherit or provide that capability.
When searching for a template with a required capability, ISP recursively chooses
templates that provide all the required capabilities.
Rules
Rules specify the criteria for allocating storage, the criteria for laying out VxVM
objects on storage, and the relationship between these objects. Rules can be
classified as storage selection rules that define how to choose storage, or as storage
layout rules that define how storage is to be used.
You can optionally precede any rule with the keyword desired. This modifier
means that ISP tries to honor this rule, but it can discard it if the rule would cause
the allocation to fail. An optional integer after the desired keyword specifies the
preference order value for the rule. If specified, this number must be greater than
or equal to 1. If no preference order value is specified for a rule, a value of 1 is
assumed. Rules with low preference order values are preferred to be retained over
rules with higher values. Rules with the same preference order are discarded
together.
In the following example, the stripe rule can be dropped if there is insufficient
storage to fulfill the storage allocation request:
mirror 2 {
desired 10 confineto "enclosure"
desired 15 stripe 15
}
Storage selection rules
The following sections describe storage selection rules:
affinity
confineto
153Using capabilities, templates and rules
Rules